Article support in oven

ABSTRACT

A bracket for supporting an article such as an unfinished artificial bridge, cap or denture having one or more sockets in the heat treatment and other processing steps is formed of a work hardenable metal which is stress relieved, nonflaking, nondistorting and forms an adherent thin protective oxide coating at the heat treatment temperature. The bracket includes a base and a plurality of upwardly directed support legs which are deformable to mate and releasably engage corresponding bridge sockets. The bracket is formed of weld connected intersecting slightly outwardly downwardly inclined horizontal rods terminating in the support legs or includes a base member having channel sections which slidably engage one or more plug members each of which is provided with a pair of support legs, or band which supports the support legs.

Bocian et al.-

[ June 25, 1974 ARTICLE SUPPORT IN OVEN [75] Inventors: Harvey Bocian, Jericho; Allan L.

Brent, Dobbs Ferry, both of N.Y.

[73] Assignee: LabcoProducts, lnc., Jamaica, N.Y.

[22] Filed: Jan. 11, 1973 [21] App]. No.: 322,768

[52] US. Cl. 432/5, 432/259 [51] Int. Cl. F27b 21/04 [58] Field of Search 432/3, 5, 6, 258, 259

[56] References Cited I UNITED STATES PATENTS 1,530,479 3/1925 Carlson 432/259 1,610,111 12/1926 Weaver 432/259 1,963,242 6/1934 Nelson 432/259 2,030,707 2/1936 McLean 432/259 2,252,963 8/l94l Fahrenwald 432/259 2,311,942 2/1943 Hagemeyer 432/259 3,324,524 6/1967 Perron et al. 432/259 Primary Examiner-John J. Camby Attorney, Agent, or Firm-Howard C. Miskin 57 v ABSTRACT A bracket for supporting an article such as an unfinished artificial bridge, cap or denture having one or more sockets in the heat treatment and other processing steps is formed of a work hardenable metal which is stress relieved, nonflaking, non-distorting and forms an adherent thin protective oxide coating at the heat treatment temperature. The bracket includes a base and a plurality of upwardly directed support legs which are deformable to mate and releasably engage corresponding bridge sockets. The bracket is formed of weld connectedv intersecting slightly outwardly downwardly inclined horizontal rods terminating in the support legs or includes a base member having channel sections which slidably engage one or more plug members each of which is provided with a pair of support legs, or band which supports the support legs.

11 Claims, 7 Drawing Figures 1 ARTICLE SUPPORT IN OVEN BACKGROUND OF THE INVENTION The present invention relates generally'to improvements in treating methods and apparatus and it relates particularly to an improved method and apparatus for the heat treating of artificial bridges attendant to the porcelainizing thereof as well as for effecting other treatments of the denture.

In the conventional production of artificial bridge, whether of the single or multiple tooth types, the unfinished bridge is initially produced by known procedures and is provided with one or more sockets in its inner end faces depending upon whether the denture is a single or multiple tooth restoration. The bridge is then subjected to numerous preparatory treatments including finishing, and porcelainizing, and post'treatments. Many of these steps require the proper'and'precise support of the bridge without imparting any stress to it and without interfering with the treatment thereof. Among the steps which are accompanied by many difficulties is the heat treatment of the bridge in effecting the porcelainizing thereof during which step the bridge is heated to a temperature not exceeding about 2,l F. The bridge, during the heat treatment must be supported ina raised'condition without any stress being imparted thereto even during the raising of the temperature thereof. The procedures and devices heretofore employed in the support and handling of the bridge during its treatment possess numerous drawbacks and disadvantages. They are fragile, heavy and absorb and retain excessive amounts of heat and often are difficult and inconvenient to employ and otherwiseleave much to be desired.

SUMMARY OF THE INVENTION It is a principal object of the present invention to provide animproved heattreating method and apparatus.

Another object of the present invention is to provide an improved method and apparatus for supporting an artificial bridge attendant to the treatment and finishing thereof.

Still another object of the present invention is toprovide an improved bracket for supporting an artificial bridge during the heat treatment thereof in the production of a porcelain coating, which bracket may be repeatedly reused and does not stress or.otherwise adversely affect the bridge.

A further object of the present invention is to provide an improved method and apparatus of the above nature characterized by their convenience, reliability, simplicity, and high adaptability and versatility.

The above and other objects of the present invention will become apparent from a reading of the following description taken in conjunction with the accompanying drawing. I Y

In a sense the present invention contemplates the provision of a method for producing an article which is heat treated at a predetermined temperature comprising forming the article in an untreated state with a pair of spaced sockets, shaping. a pair of work hardenable metal legs of a support bracket to bring the ends thereof into engagement with the sockets and thcreat? ter subjecting the article and bracket to said predetermined temperature for a time sufficient to stress relieve 2 the metal legs and affect the heat treatment of the article. The bracket, per se, is within the scope of the pres ent invention and comprises a base member and a plurality of legs terminating in upwardly directed plug portions for engaging mating sockets in a work piece, the legs being formed of a bendable, work hardenable metal which is stress relieved at a temperature not exceeding 2,100 F. and is heat distortion free at said temperature.

In accordance with a preferred form of the improved bracket there are provided a plurality of rods of a nickel, chromium, iron alloy whose composition will be hereinafter described, each of the rods being shaped to include a horizontal arm terminating at opposite ends in upwardly directed plug definite legs, one of the legs being joined to the arm by a U-shaped section. The horizontal arms are angularly related and cross each other, being mutually affixed, such as by welding at their points of intersection. Another form of bracket according to the present invention comprises a base member including a pair of transversely spaced horizontal channels with confronting openings and joined to each other by cross rods or undulating cross pieces connecting the channel bottom flanges. One or more plug members are provided, each including a cross-piece extending between and slidable along the channels and a pair of spaced upwardly directed legs.

The improved method and apparatus are reliable, simple, convenient and of great versatility and adaptability. Moreover, by reason of the low mass of the ap paratus and its structure the effect thereof on the oven temperature isminimal resulting in optimum heating conditions, and the cooling of the apparatus upon removal from the oven is rapid by reason of the small heat retention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bracket embodying the present invention and which is advantageously employed in practicing the improved process;

FIG. 2 is a top plan view thereof showing one of the arms bent to accommodate a work-piece illustrated by brokenlines;

FIG. 3 is a perspective view of the base section of another embodiment of the present invention;

FIG. 4 is a perspective view of a modified form of base section;

FIG. 5 is a perspective view of a separable leg section employed with the base sections shown in FIGS. 3 and FIG. 6 is a perspective view of the assembled leg and base sections shown in FIGS. 4 and 5; and

FIG. 7 is a perspective view of another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS downwardly outwardly inclined almost horizontal main section 12 bent about 180 at one end thereof to form a horizontal or vertical U-shaped section 13 including a horizontal arm 14 extending inwardly parallel to main section 12 and horizontally or vertically or angularly spaced from section 12. Projecting vertically upwardly from the free end of arm 14 is a first plug defining leg 16 and projecting vertically upwardly from the opposite end of main bracket members 12 is a second plug defining leg 17. The bracket member 12 are arranged in quadrature with opposite bracket members 12 of one pair being laterally spaced and crossing and overlying the other transversely spaced pair of bracket members 12. The intersecting points of the bracket member sections 12 are proximate the legs 17 and delineate the corners of a square, the bracket member sections 12 being welded or otherwise joined to each other at their points of intersection which are somewhat above the outer ends of sections 12.

The bracket members 11 are formed of a bendable work hardenable metal which is stress relieved at a temperature not exceeding the heat treatment temperature at which the bracket is to be employed advantageously at a temperature not exceeding 2,lO F., and is heat distortion free at this temperature. Furthermore, the metal is stable at the heat treatment temperature and forms at a temperature not exceeding this temperature, an adherent, non-flaking, thin oxide coating which inhibits any further oxidation of the underlying metal. An example of a metal alloy which may be employed to great advantage is one which possesses primarily the following nominal composition in addition to other elements in very minor amounts:

Nickel Chromium lron The bracket may be employed in the production of one or more single tooth or multiple tooth artificial bridges as shown in FIGS. 1 and 2 respectively, or both simultaneously. In practicing the present improved method in the production, for example of a multiple tooth bridge 18, the unfinished bridge 18 is produced in any suitable or conventional manner and is provided with a pair of sockets in the inside end faces of the end teeth. One or a pair of leg sections 12 which are in soft malleable states are bent to bring their legs 16 into aligned registry with the end sockets in bridge 18, the legs which are bent, being hardened as a result of the working thereof. The legs 16 are then inserted into engagement with the sockets to support the bridge 18 in an upright convenient position. The bridge, while supported by bracket '10, may be subjected to numerous treatments including preparatory treatment including finishing and porcelainizing and post treatment and one or more heating steps, at least one of which effects the fusion of the porcelain composition and is advantageously effected at a temperature never to exceed 2,l00 F. During at least one of the heating steps the bracket elements 11 are stress relieved and the elements 11 are heat distortion free even at the final firing stage.

After the final treatment of the bracket supported bridge 18 it is removed from the bracket 10 and the bracket 10 may then be used in the above manner for the treatment of other dentures in the manner described above. The bracket 10, following the heating stages, has returned to a condition wherein the elements 11 are easily workable and bendable to accommodate other dentures. It should be noted that one or more single or multiple tooth dentures may be supported by the bracket 10, the most convenient legs 16 being employed for each bridge.

In FIGS. 4 to 6 there is illustrated another embodiment of the present invention for practicing the improved method, the modified bracket 20 including a base member 21 and one or more plug members 22. The base member 21 includes a pair of opposite transversely spaced, parallel, track defining longitudinally extending channel members 23 having confronting openings and parallel top and bottom legs or flanges 24 and 26 respectively. Suitably affixed to the underfaces of bottom flanges 26, such as by welding, are a plurality of longitudinally spaced transversely extending parallel rods 27.

The plug member 22 includes a narrow cross piece 28 formed of flat plate and terminating at its ends in outwardly directed pointed tips 29, the distance between the tips being approximately equal to the inner faces of the elbows 30 of channel members 23. Mounted atop cross piece 28 are a pair of symmetrically laterally spaced upwardly directed rod shaped legs 32, the distance between the outer faces of which is slightly less than that between the confronting inner edges of opposite flanges 24. The base member 21 and the plug member 22 are formed of a metal similar to that forming the bracket 10 described above. In employing the modified bracket 20 one or more of the plug members 22 are coupled to base member 21 by sliding the plug member across pieces 28 into engagement with opposite channel members 23, as shown in FIG. 6, and adjusting them to accommodate the sockets in the dentures to be treated by sliding the plug members 22 along the base member 21 and if necessary, bending the legs 32. In all other respects the operation and use of the bracket 20 is similar to those of bracket 10, as described above.

A base member 33, illustrated in FIG. 3 of the drawing, is integrally formed of sheet metal of the type used in forming brackets 10 and 20, and may be substituted for the base member 21 for use with plug members 22. The base member 33 comprises a pair of opposite parallel channel members 34 similar in structure and disposition to channel members 23, each channel member 34 including top and bottom flanges 36 and 37 respectively. Extending between and integrally formed with the opposing ends of opposite bottom flanges 37 are foot piece define undulating cross members 38. The cross members 38 include transversely spaced upper horizontal cross legs 39 coplanar with or slightly below the level of bottom flanges 37 and transversely spaced lower horizontal coplanar cross legs 40, below the level of cross legs 39, the cross legs 39 and 40 being interconnected by vertical legs 41. The cross members 38 are advantageously resiliently extendable. The base member 33 is employed with one or more plug members 22 in the manner of base member 21.

Another embodiment of the present invention is illustrated in FIG. 7 of the drawing in which the improved bracket 50 is formed of a metal similar to that of the earlier described brackets. The bracket 50 includes a horizontal triangular frame 51 formed of a metal band,

I said metal legs.

the arms 52 of the frame 51 lying in vertical planes and preferably being of equal lengths. Welded to each of the inside corners of the frame 51 is a vertical leg 53 which projects above and below the level of frame 51, the bottoms of legs 53 lie in a horizontal plane and the legs 53 may be of equal lengths. Also welded to the inside face of each of the frame arms 52 are one or more longitudinally spaced vertical legs 54 which project above the level of the frame 51..

The use and application of the bracket 50 are similar to those of bracket as earlier described.

While there have been described and illustrated preferred embodiments of the present invention it is apparent that numerous alterations, omissions and additions may be made without departing fromthe spirit thereof.

What is claimed is:

l. The method for producing workpiece defining article which is heat treated at a predetermined temperature comprising forming said workpiece in an untreated state with a pair of spaced socket defining wells, trans versely adjusting a pair of work hardenable metal legs of a support bracket to bring the ends thereof into registry with said sockets and inserting said ends into engagement with said sockets and thereafter subjecting said workpiece and said bracket to said predetermined temperature for a time sufiicient to stress relieve said metal legs and effect the treatment of said workpiece.

2. The method of claim 1 wherein said predetermined temperature is below the heat distortion point of 3. The method of claim 1 wherein said predetermined temperature is about 2,l00 F.

4. The method of claim 1 including subjecting the bracket supported article to mechanical finishing operations prior to the heating thereof.

5. A high temperature heat treating work support bracket comprising a base member and a plurality of upwardly directed continuously relatively transversely adjustable legs terminating in upwardly directed plug portions for engaging mating sockets in a workpiece, said legs being formed of a bendable work hardenable 7. The bracket of claim 6 wherein said metal is an alloy of approximately the following composition:

Component Percent Nickel 6 l Chromium 23 Iron 14 In addition to other elements in very minor amounts.

8.'The bracket of claim 5 wherein said base comprises'a plurality of rods crossing and joined to each other between the ends thereof and said legs are integrally formed with said base rods and terminate in said upwardly directed plug portions.

9. The bracket of claim 5 wherein at least some of said legs include U-shaped sections each of which includes an arm joining an upwardly directed leg terminating'in said plug portion.

10. The bracket of claim 5 wherein said base member comprises a horizontal frame member and said legs are secured to and longitudinally spaced along and project above said frame member, at least three of said legs extending below the level of said frame member.

11. A high temperature heat treating work support bracket comprising a base member including a pair of parallel channel shaped track having top and bottom parallel flanges and undulating cross pieces extending between and integrally formed with and projecting below said bottom flanges, a cross piece slidably engaging said tracks and a plurality of legs mounted on and directed upwardly from said slidable cross piece and terminating in upwardly directed plug portions for engaging mating sockets in a work piece, said legs being formed of a bendable work hardenable metal which is stress relieved at a temperature not exceeding 2,l00 F.

and is heat distortion free at said temperature. 

1. The method for producing workpiece defining article which is heat treated at a predetermined temperature comprising forming said workpiece in an untreated state with a pair of spaced socket defining wells, transversely adjusting a pair of work hardenable metal legs of a support bracket to bring the ends thereof into registry with said sockets and inserting said ends into engagement with said sockets and thereafter subjecting said workpiece and said bracket to said predetermined temperature for a time sufficient to stress relieve said metal legs and effect the treatment of said workpiece.
 2. The method of claim 1 wherein said predetermined temperature is below the heat distortion poinT of said metal legs.
 3. The method of claim 1 wherein said predetermined temperature is about 2,100* F.
 4. The method of claim 1 including subjecting the bracket supported article to mechanical finishing operations prior to the heating thereof.
 5. A high temperature heat treating work support bracket comprising a base member and a plurality of upwardly directed continuously relatively transversely adjustable legs terminating in upwardly directed plug portions for engaging mating sockets in a workpiece, said legs being formed of a bendable work hardenable metal which is stress relieved at a temperature not exceeding 2100* F. and is heat distortion free at said temperature.
 6. The bracket of claim 5 wherein the metal forming said legs is non-flaking and forms an adherent protective oxide coating at said temperature.
 7. The bracket of claim 6 wherein said metal is an alloy of approximately the following composition: Component Percent Nickel 61 Chromium 23 Iron 14 In addition to other elements in very minor amounts.
 8. The bracket of claim 5 wherein said base comprises a plurality of rods crossing and joined to each other between the ends thereof and said legs are integrally formed with said base rods and terminate in said upwardly directed plug portions.
 9. The bracket of claim 5 wherein at least some of said legs include U-shaped sections each of which includes an arm joining an upwardly directed leg terminating in said plug portion.
 10. The bracket of claim 5 wherein said base member comprises a horizontal frame member and said legs are secured to and longitudinally spaced along and project above said frame member, at least three of said legs extending below the level of said frame member.
 11. A high temperature heat treating work support bracket comprising a base member including a pair of parallel channel shaped track having top and bottom parallel flanges and undulating cross pieces extending between and integrally formed with and projecting below said bottom flanges, a cross piece slidably engaging said tracks and a plurality of legs mounted on and directed upwardly from said slidable cross piece and terminating in upwardly directed plug portions for engaging mating sockets in a work piece, said legs being formed of a bendable work hardenable metal which is stress relieved at a temperature not exceeding 2,100* F. and is heat distortion free at said temperature. 